About a year ago I needed a new printer and noticed that color laser printers had become quite affordable, around €500. So I got a HP Color LaserJet CP1515n that I am quite happy with. I don't usually print a lot, so I didn't worry much about the toner. This year I started dungeon master this D&D campaign, and suddenly I am printing a lot: Character sheets, battle maps, handouts, self-written adventures, the lot. So unsurprisingly at one point my toner was heading for empty. So I went and bought a complete set of original toner cartridges, and was surprised that this cost we two thirds of the price of the printer!
Closer examination revealed that this wasn't quite the "buy a new printer when the toner is empty" deal I feared. The CP1515n has a nice function where you can print out a page with a lot of detail on the status of the toner directly from the printer's front panel menu. And once I put a new cartridge in it showed up as being 100% full with an estimate of this being enough for 1400 pages. The cartridges that came with the printer could only do 700 pages when 100% full, so those were half-sized.
If I wanted to save money, I could always buy "rebuilt" toner cartridges which only cost half of what the original cost. But I did that for my previous black & white laser printer, with the result that once on unpacking the rebuilt toner cartridge I had black toner spilled all over my office.
Anyway, if I take original toner and it really gives me 1400 pages per set of toner, my total cost of printing in full color will be under 25 cents per page. I tried to do some research with Google whether that was a typical cost, but quickly found out that printing cost per page is extremely hard to measure. It depends too much on what you print. A printout of a web page with mostly text and just a bit of colored graphics costs a lot less toner than printing a photo or one of my battle maps, where the toner completely covers the page. During my last play session somebody spilled some of his drink on one of my maps, and it turned out that the coat of toner was dense enough to make the paper water-repelling. I'm afraid the "1400 pages" estimate is more for some standardized color page with 20% coverage than my 100% coverage battle maps, which could drive my cost per map to over €1 per page.
Well, I'm a bit of a map-fanatic, so I don't mind the cost. But I had previously assumed that playing pen & paper would be much cheaper than playing a MMORPG, and now I'm not so sure any more. I do think that a pen & paper campaign gains a lot by having lots of maps and printed handouts, but I might well end up paying more for those than $15 a month for a MMORPG. Well, still either hobby is a lot cheaper than the hobbies other middle-aged men waste their money on. ;)